Pneumatic dispatch signaling system



June 14, 1949- D. w. G. McCLURE 72 PNEUMATIC DISPATCH SIGNALING SYSTEM Filed Dec. 13, 1944 A T TOR/V575 INVENTVOR Patented June 14, 1949 UNITED STATES PATENT orncs PNEUMATIQDISPATCH SIGNALING SYSTEM Dott W-,G!.Mo0 ur P ena, Calif" assignor to Consolidated Engineering Corporation, Pasadena, Calif a corporation of California Application December 13, 1944.,Se1'ialN0- 568, 36

4 Claims. 1

This invention relates todeli ery system s oh as the pneumatically-Op ed ty e in wh a receptacle is sent through a delivery tube from a sending station to a receiving station. The principal object is to provide in cooperation with such systems a signalin means for indicating receipt at the delivery end.

There are in common use pneumatically-operated systems for sending a cylinder or other carrier through a delivery conduit or tube from a sending end to a receiving end. Such systems operate by the application of air pressure or vacuum into the tube on the receptacle; this pressure or vacuum being applied by the'sender at the sending end until the carrier element is delivered at the receiving end. For this purpose, it is convenient and desirable for the operator at the sending end to know when the carrier is'received at the receiving end. It has heretofore been difiicult to arrange a signaling system which will signify the receipt of the carrier at the receiving end, due to the fact that the carrier is traveling so fast that it does not have time to make a prolonged contact with any part of the system such as would enable a good electrical signal to be transmitted to the sending end.

In accordance with my invention, I have ar' ranged a device for enabling an electricalsignal such as an annunciator buzzer to .be actuated at the sending end from. operation of a switch at the receiving end when the carrieris received. I have done this by the provision withintheconveyor tube at the receiving end of an elongated flexible strip extending longitudinally of theconduit and depressed while the carrier ispassing it. As this strip has considerable length, it remains depressed for an appreciable time while the carrier is passing and is thus enabled to operate a switch for this appreciable time, whereby the signal is given at the sending end for an appreciable duration.

According to a preferred feature of my in-. vention, I construct the elongated strip in two iii Parts, the initial part :being a resilient flexible portion, and the remaining part extending for the major portion of the strip, being of a stiffer construction.

According to a further feature of my invention, the elongated strip may be adapted not only to operate the switch, but alsoto act as a brake for the carrier.

The foregoing and. ther features or, my in on tion will be understood from the followin li tailed description and the accompanying drawing, of which: I

Fi 1 shows partially in section the sending and receiving nolsof a pneumatical yperated carrier conduit, the conduit being provided with a signalin system according to my invention;

Fig, 2 s s a cr s-sectional vi w taken at line 2+2 oi Fig. 1;, and

g. .3 shows a arrier element dapted to be transmitted throu h the tube.

Referring o Fig. l, th pneuma ic stem. om prises the usual tube conduit I through h ch is adap ed to be c nv yed a carrier member 2 of the general cy ndrical shape shown i ig 3.. This is shown with a, washer 2a o act a a seal against the conduit wall. The conduit has t o end 3 and .4 and the carrier member 2 is adapted. to be conveyed f om. either end to th other y pneumat c p essure. There is provided for t and .3 of the conduit a cover memb r 6 provideo with a rubber gasket 1;. and the pneumatic convey n pressure is provided th ough. a t be 5 attached through the cover 6. The a an ement is such. that when the cover mem er is placed in position ov r the nd of the co du t}, air from. ube 5 may be sent into the en 3, y operation of a uitable valv (no h h and. blown through the tubular conduit l and out the other end 4. F r thi purpose, the over m m e .6 at e d 4 is left hang ng o f t e end of the conduit as shown in ig.- so that he carrier tub pa ses freely out of th e 4 and drops into .a suitab e bask t or o her re p acl When the car ier has thus mp e ed i p through the conduit, the operator at end 3 then removes cover 6 so t at he sys em is ada ed to send he ar i r bo k in th reverse d e on from end 4. When the operator at end 4 desires to sendthe carrier 2 back again, he inse ts i in o th end 4 ir m the bo tom andlapp ies the cover 6' of the end o t e Conduit in the p ition own at nd so that air rrom blow r 5 w l low t back through the conduit to e d 3 where it is free to drop out into a suitable basket, ascover 6 is now removed,

Regardless of which way the, carrier member 2 is sent, the operator at the end from which it is sent must keep the cover on to keep up the air pressure in the conduit until the carrier drops out at the receiving end. In order that the operator at the sending end may knowwhen it arrives atthe receiving end so that he may then remove his cover to put his end in condition to receive the carrier, there is provided an electrical signal ing system. This comprises a suitable indicator such as a bell or a buzzer at each end of the conduit thebuzzer at. one end being designated 8 and the bell at the other end being designated 8. Each bell or buzzer is adapted to be operated from a source of electrical voltage which is ordinarily a 60-cycle supply line. This supply line is shown connected to the terminals 9 and 9A of the primary winding of a transformer T, for stepping down the .voltage to an appropriate voltage for operating the buzzer. The terminals II! and IDA of the secondary winding of the transformer are connected in series with a switch S and the buzzer terminals II and HA. Thus when switch S is closed, the buzzer 8 is operated.

For the purpose of operating switch S, I provide within the conduit l and near the end 4 a flexible operating member l2. This comprises a flexible strip I3, for example of a thin flexible steel or bronze, fastened at its upper end to the inside of the conduit by a suitable fastening device such as the nut and bolt arrangement I4. The lower end of strip l3 extends inwardly into the conduit from the conduit wall and the strip is flexible enough so that it can readily be sprung back against the wall. There is fastened to the lower end of strip l3, for example by welding or soldering at Ma, a considerably thicker and stiffer strip l5. Strip I5 hangs downward from strip l3 inside the conduit at some distance from the inner conduit wall, for example, a quarter of an inch or so. The strip I5 is brought back against the conduit wall at the lower end of the conduit, where an L-shaped portion H, of the strip is in contact with the inner surface of the conduit and is brought around beneath the lower end of the conduit to form a hook at l8 adapted to hook into a corresponding recess l9 formed at the end of the conduit. The recess l9 may conveniently be formed in the lower outer end of a collar member 20 placed around the lower end of conduit l. The length of the resilient portion l3 of the strip may conveniently be in the neighborhood for example, of about five inches, and the length of the rigid portion [5 may be for example, about eighteen to twenty-four inches, the length required being determined somewhat by the speed of the carrier at the strip in the particular installation involved.

For the purpose of operating the switch, there is provided a pin 2| slidably placed within a guide 22, threaded into the collar 20 and protruding into the conduit so that the inner end of the pin extends into the conduit and the outer end of the pin protrudes toward a lever 23 mounted on the switch box.

The switch S comprises a fixed switch element 24 and a movable switch element 25, the latter being in the form of a pin attached to switch lever 23, so that when lever 23 is pressed by pin 2|, the contact pin 25 will be moved into contact with switch member 24. For convenience, the switch box S is mounted in a suitable manner on a mounting member 26, which can conveniently be made of sheet metal wrapped around the conduit, just above collar 20, with the two ends 26A brought out fiat and facing each other at some distance apart and bolted together by suitable bolts 21. A platform 28 is fastened in a suitable manner (not shown) to the upper edges of members 26A. On this platform is mounted a suitable bed of rubber 29 on which is mounted the buzzer 8'. The terminals 30 and 3| of switch S are connected over wires 32 and 33 to transformer terminal IDA and terminal H of buzzer 8 respectively, as described above, to complete the circuit from switch S to buzzer 8.

The lefthand end of conduit I is provided with a switch mechanism similar to that shown at its righthand end in cross-section. Thus, the collar 20 corresponds with collar 20 and member 26' corresponds with member 26. There is similarly provided a switch S corresponding to switch S with its resilient switch arm 23 corresponding to arm 23. Lever 23' is operated by the slidable pin 2| arranged in a manner similar to pin 2|; and there is provided within this end of conduit I an elongated strip similar to strip I2, this strip being held at its upper end by a bolt l4 corresponding to bolt I4.

In operation, when the operator at the left end of the conduit wishes to send the carrier 2 to the right end, he inserts the carrier up into the bottom of conduit I while the cover is removed. Then he applies the cover 6 in the position shown in Fig. 1 and applies the compressed air so that the carrier is sent through the conduit to the receiving end. In passing the strip held by bolt l4, the switch S will be closed, sending current from the secondary of transformer T to the buzzer 8. This may serve a useful purpose, if it is desired to inform the person at the receiving end that the carrier is coming. Then when the carrier approaches the receiving end, it contacts strip l3 and flexes it against the inner surface of the conduit, thereby bodily moving the hanging heavier strip l5 toward the conduit wall, causing it to push pin 2| against switch lever 23. This moves switch member 25 into contact with 24, thereby closing the circuit through buzzer 8 and announcing to the sender that the carrier has been received.

The stiff strip l5, in addition to acting as an elongated switch-operating strip, serves the additional function of acting as a brake for the carrier. In a carrier system of the type described, the carrier is often traveling at a high rate of speed when it reaches the sending end, so that it tends to bounce out of the receiving basket or receptacle. By bowing the stiff strip l5 somewhat however, it lies somewhat in the path of the carrier even after the thin resilient strip [3 has been sprung against the conduit wall. The heavy strip 15 thereby tends to act as a brake for the passing carrier and slows it down to a more desirabie receivin speed. The passage of the carrier may tend to straighten out strip IS a little bit, but it is held in place at the bottom of the conduit by reason of the hook l8 which remains hooked at recess l9.

When the person at the right end desires to send the carrier back again, he inserts it in the open end of the conduit at his side, and applies the cover (5' and turns on the compressed air to send the carrier back again, In traveling back, the carrier depresses member 15 at the beginning of its trip to operate buzzer 8 and then when it reaclizcs the other end of the conduit, it operates the member held by bolt M to ring buzzer 8.

It will be recognized that by my invention, I have provided a mechanical arrangement which enables an indicating device to be operated for an appreciable length of time by a rapidly moving carrier device. The arrangement is furthermore adapted to act as a brake for the carrier if it should be movin too fast.

-lthough my invention has been described with particular reference to the pneumatic-pressure type of system disclosed in the detailed description, it will be understoodthat it can also be used with other typa of carrier systems, such as the vacuum-operated type.

I claim:

1. In a pneumatic conveyor system, the combination which comprises a conduit of substantially uniform cross section, a carrier slidably fitted within the conduit, a brake in the form of a long leaf spring mounted lengthwise in the conduit with a substantial portion of its length bowed into the path of the carrier in the conduit but depressable out of the path by the sliding carrier, the spring being sufiiciently strong to decelerate the sliding carrier substantially, and a switch having a contactor that is operated by the brake, the contactor being disposed behind the leaf spring in the conduit wall and movable transverse to the wall an d so that the spring, on bein depressed by the sliding carrier, touches the conta-ctor for a substantial portion of the period during which the carrier is in contact with the spring.

2. In a pneumatic conveyor system, the combination which comprises a conduit of substantially uniform cross section, a carrier slidably fitted within the conduit, a brake in the form of a long leaf spring mounted lengthwise in the conduit adjacent an end thereof with a substantial portion of its length bowed into the path of the carrier in the conduit but depressable out of the path by the sliding carrier, the spring being sufficiently strong to decelerate the carrier substantially and one of its ends being free to move longitudinally in the conduit, and a switch having a contactor that is operated by the brake, the contactor being disposed behind the leaf spring adjacent the conduit wall in such position that the spring, on being depressed by the carrier, touches the contactor for a substantial portion of the period during which the carrier is in contact with the spring.

3. In a pneumatic conveyor system, the combination which comprises a conduit of substantially uniform cross section, a carrier slidably fitted within the conduit, a brake in the form of along leaf spring mounted lengthwise in the conduit adjacent an end thereof with a substantial portion of its length bowed into the path of the carrier in the conduit but depressable out of the path by the sliding carrier, the spring being sufficiently strong to decelerate the carrier substantially, the end of the spring remote from the end of the conduit being anchored to the conduit and the other end being free to move longitudinally, and a switch having a contactor that is operated by the brake, the contactor being disposed behind the leaf spring adjacent the conduit wall in such position that the spring, on being depressed by the carrier, touches the contactor for a substantial portion of the period during which the carrier is in contact with the spring.

4. Apparatus according to claim 3 in which the end of the spring anchored to the conduit is thinner and less stiff than the balance of the spring.

DOTT W. G. MCCLURE.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS 

